ΔE 23.4, loose: different enough that you should pick on purpose. Celestial Violet is noticeably darker, more saturated, warmer than Dark Metallic Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Celestial Violet is noticeably darker, more saturated, warmer than Dark Metallic Blue.
The same difference applies the other way round: Dark Metallic Blue is noticeably lighter, more muted, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Dark Metallic Blue on the colour wheel See Celestial Violet on the colour wheel
All matches: Dark Metallic Blue equivalents · Celestial Violet equivalents